A Thin Film Transistor Liquid Crystal Display (TFT-LCD) is light, thin and small, and further has low power consumption, no radiation, low costs and other merits, thus dominating the current flat panel display field. The TFT-LCD is suitable for desktop computers, palmtop computers, Personal Digital Assistants (PDAs), cellular phones, televisions and various kinds of office automation devices and audio-visual devices. A liquid crystal display panel is a main component of the TFT-LCD, and usually includes a TFT array substrate (also called an array substrate), a color filter substrate and a liquid crystal layer between the TFT array substrate and the color filter substrate.
An array substrate in a conventional TFT-LCD usually includes a plurality of data lines and a plurality of scanning lines, and the data lines and the scanning lines intersect to define a plurality of pixel regions. A pixel electrode is formed in each pixel region, and a common electrode line is configured at a layer below a layer in which the pixel electrode is located. The pixel electrode and the common electrode line overlap and there is an insulation layer between the pixel electrode and the common electrode line, to form a storage capacitor in the pixel region. A TFT is configured near the intersection location of a data line and a scanning line, and includes a gate electrode, a semiconductor layer, a source electrode and a drain electrode. Generally, the gate electrode of the TFT is electrically connected with the scanning line, the source electrode is electrically connected with the data line, and the drain electrode is electrically connected with the pixel electrode.
Although the TFT-LCD dominates the flat panel display field at present, there are still technical problems with LCD panels, e.g., a wide viewing angle problem. That is, when a user watches an image respectively from directly in front of a screen versus at an angle to the screen, the image has different gray scales and brightness. Generally, the brightness of the image watched from straight ahead of the screen is higher than that of the image watched from an angle. A LCD panel which adopts a negative liquid crystal material with negative dielectric anisotropy and has a vertical alignment (VA) manner can provide a good contrast ratio because liquid crystal molecules are arranged vertically to the substrate when no voltage is applied. However, in order to achieve a multi-domain division effect, a VA type LCD usually has a problem of light leakage, which has an adverse impact on improving the contrast ratio of the LCD panel.
Referring to FIGS. 1 and 2, FIG. 1 is a schematic diagram illustrating a pixel structure of a conventional Multi-domain Vertical Alignment (MVA) type LCD panel, and FIG. 2 is a sectional view of the MVA type LCD panel along an A-A′ line in FIG. 1. As shown in FIG. 2, the LCD panel mainly includes a TFT array substrate on a lower layer, a color filter substrate 80 on an upper layer, and liquid crystal molecules 70 between the TFT array substrate and the color filter substrate 80. There is a common electrode 81 on the color filter substrate 80. As shown in FIG. 1, the intersection of two adjacent scanning lines 10 and two adjacent data lines 20 define a pixel region. A pixel electrode shown in FIG. 1 includes two sub-pixel electrodes 30 and 40. In the MVA type LCD panel, slits 60 are usually configured on the TFT array substrate and bumps 50 are configured on the color filter substrate 80, so that the liquid crystal molecules 70 have pre-tilt angles towards different directions when no voltage is applied. In this way, the inclining direction of the liquid crystal molecules can be controlled effectively and rapidly after a voltage is applied. After the voltage is applied, the liquid crystal layer can be divided into multiple liquid crystal micro-domains with different inclining directions, so that viewing angle characteristics in gray scale display states watched from different viewing angles can be improved. However, to configure the bumps 50 on the color filter substrate 80 usually results in light leakage, which reduces the contrast ratio of the LCD panel. Furthermore, it is necessary to use a photo etching technology to form the bumps on the color filter substrate, which makes the manufacture process complex and increases costs.